Protein-Sparing Modified Fast (PSMF) Guidelines 

This diet is good for:
• Rapid fat loss
• Seeing results and building motivation
This diet is NOT good for:
• Long-term wellness
• Increasing energy
• Boosting metabolism
• Athletic performance
• Building muscle
• Strength gain

Protein-Sparing Modified Fast (PSMF) Guidelines

A protein-sparing modified fast (PSMF) is a very low-calorie diet (less than 1,000 calories per day) that involves significantly limiting the intake of calories, carbohydrates, and fat while increasing protein consumption. This is a temporary diet designed to kick-start rapid fat loss. The idea of a PSMF is to reduce calories to the lowest possible threshold while still eating enough protein to preserve lean muscle mass and taking in enough key micronutrients to avoid deficiency. A PSMF should only be used for up to eight weeks before transitioning back to a sustainable long-term GRx diet.

Allowed foods (eat as much as you are hungry for): 

  • Lean red meat: all lean cuts of beef (no ribs and rib eye), veal, buffalo, venison, ostrich 
  • Organ meats: liver, kidneys, heart, tongue 
  • All poultry, except duck and goose (but without skin) 
  • Lean pork 
  • All fish: fatty, lean, white, oily, raw, or cooked 
  • All shellfish 
  • Eggs 
  • Nonfat dairy products (if tolerated) 
  • Non-starchy vegetables, raw or cooked 
    • Amaranth or Chinese spinach
    • Artichoke
    • Artichoke hearts
    • Asparagus        
    • Baby corn
    • Bamboo shoots
    • Beans (green, wax, Italian)
    • Bean sprouts
    • Beets
    • Brussels sprouts
    • Broccoli
    • Cabbage (green, bok choy, Chinese)
    • Carrots
    • Cauliflower
    • Celery
    • Chayote
    • Coleslaw (packaged, no dressing)
    • Cucumber
    • Daikon
    • Eggplant
    • Greens (collard, kale, mustard, turnip)
    • Hearts of palm
    • Jicama
    • Kohlrabi
    • Leeks
    • Mushrooms
    • Okra
    • Onions
    • Peapods
    • Peppers
    • Radishes
    • Rutabaga
    • Salad greens (chicory, endive, escarole, lettuce, romaine, spinach, arugula, radicchio, watercress)
    • Sprouts
    • Squash (cushaw, summer, crookneck, spaghetti, zucchini)
    • Sugar snap peas
    • Swiss chard
    • Tomato
    • Turnips
    • Water chestnuts
    • Yard-long beans
  • Extras: coffee, tea, vinegar, natural flavorings, spices, herbs, pickles, sauerkraut, lemon, salt, mustard (gluten-free) 

Other guidelines: 

  • Aim for a daily intake of 1 gram of protein per pound of bodyweight
  • Eat at least one pound of fatty fish per week (salmon, sardines, mackerel, herring) to ensure adequate omega-3 intake 
  • Drink half your body weight in ounces of water per day. For example, if you are 200 pounds, drink 100 ounces of water a day.
  • If constipation is a problem, take a prebiotic like Biotagen from Klaire Labs. Start at a small dose and build up slowly over time since prebiotics can cause gas and bloat initially. 
  • Consume fermented vegetables like sauerkraut, kimchi, sauerruben, and a probiotic to maintain beneficial gut flora.
  • If doing PSMF for more than two weeks, take a high-quality multivitamin like Nutrient 950 with Vitamin K from Pure Encapsulations.   
  • Two free meals a week are permitted if necessary. This isn’t your chance to binge on junk food, but instead to eat a normal amount of carbohydrate and fat during your meal (e.g., 1-2 sushi rolls or an 8oz rib eye with sweet potato and butter). 
  • Average weight loss on PSMF is one pound every three to four days; some go faster, some slower. 
  • Do PSMF until target weight is achieved, or two months, whichever comes first. If you notice signs of significant fatigue, stop immediately.
Burn Phase 1 | Diet

Protein-Sparing Modified Fast (PSMF) Guidelines

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